I just checked your RSS feed and it looks like all of your posts are showing up. The latest post I see (both on your blog and in the RSS feed) is called “Was habe ich denn nun?” – Über Diagnosen in der Psychotherapie.
Is there another post that is not showing up in your feed?
Yes, it is. The RSS feed isn’t generated until a viewer who isn’t you visits the blog. And there are sometimes reports of slowdowns, but not very major ones, depending on the state of the internet at the time.